Electrical switch



May 3, 1932. 1. E. JEwE-TT ELECTRICAL SWITCH 2 Sheets-Sheet Filed Jan. 3l, 1950 May 3, 1932- J. E. `nwi-:TT 1,856,254

ELECTRICAL SWITCH Filed Jan. 3l, 1930 2 Sheets-Sheet 2 s n* y Si' f7 MM2 4f /7 Patented May 3, 1932 UNITED STATES ATENE' FFlCE JOSEPH E. JEWETT, OF BUFFALO, NEW YORK, ASSIGNOR TO NATIONAL ANILINE AND CHEMICAL COMPANY, NO., OF NEW YORK, N. Y., A CORPORATION OF NEW YORK ELECTRICAL SWITCH Application led January 31, 1930.

The present invention relates to an electric switch particularly adapted for carrying a low voltage current of high amperage.

One object of the resent invention is the design of a switch W ich has a large area of contact, whereby Contact resistance is reduced t a minimum. A further object of the invention is the design of a multiple blade knife switch wherein all contact lades are l0 held clamped against the same side of the switch assembly. Another object is the provision of a multiple blade switch of resilient construction which is compact and durable. Still another object is the provision of a switch whereby an electrical apparatus connected in series with other apparatus may be cut out without interferingr with the operation of the other apparatus. Another object is the utilization of the bus bars of an electrical circuit as a part of the switch mecha` nism. These and other objects will be apparent from a consideration of the following description taken in connection with the accompanying drawings wherein, Figure 1 shows a plan view of a switch embodying the invention with parts removed; Figure 2 is a side elevation of Figure 1 with parts broken away; Figure 3 is a section taken on line 3 3 of Figure 1; Figure 4 is an end elevation of Figure 2; Figure 5 is a section taken on line 5 5 of Figure 2; Figure 6 is a section taken on line 6 6 of Figure 2; Figure 7 is a section on line 7 7 of Figure 2; and Figure 8 is a section on line 8 8 of Figure 3.

Referring to the drawings, the numeral 1 indicates the base plate casting having a generally plane top. lfntegrally cast with the base plate are the upright supports 2, 2, 3, which are arranged in pairs facing each other. Since the uprights 2, 2, and 3, 3', are identical, the description for one pair will suffice for both pairs. The supports 2, 2 and 3, 3 are cast hollow and consist of vertical walls 4, 4 having the holes 5, 5 drilled therein in alinement, and are reinforced by the side ribs 6. The top ribs 7 have the tapped holes 8, drilled therein. A series of bus bars 9 tapered upwardly on their outer faces, shown as four in number but which may be of any desired number, are shown passing between Serial No. 424,912.

the series of upright supports 2, 2, and 3, 3, and terminating at the far side of uprights 2, 2. rl`he bus bars are insulated from contact with the base plate by the bottom insulation plates 10 and side insulation plates 11. A series of bus bars 12, also upwardly tapered, of opposite polarity pass across the top of the base plate between the upright supports 2, 2 and 3, and are alternately spaced with respect to bus bars 9. Bus bars 12 terminate at the far end of uprights 3, 3 and are insulated from contact with the base plate by the insulation plates 10 and 11, similarly to bus bars 9. Preferably, the bus bars 9 and 12, which form the break aws of the switch, as shown in Figure i', are split vertically through their longitudinal centers and bowed outwardly to provide a resilient and flexible series of jaws.

Cylindrical headed bolts 13 pass through the holes 11 in the side insulation plates 11, through the insulation sleeves ll seated in the holes 15, 15 in the bus bars 9 and 12, respectively, and through the insulation spacing v washers 16 and holes o, 5 1n the uprights 2, -7'

tical or lateral movement thereof, and bear against the insulation plates 11 which bear against tie outer bus bars. Nuts threaded on the outer ends of the bolts 13 draw the assembly againstthe uprights 2, 3. Because of the bowed split construction of the bus bars. there is some resiliency between them. The bus bars 9 and 12 are further held against vertical displacement by the pair of clamping plates 17, each of which is bored at its outer ends as indicated by the numeral 18. The plates 1T are held clamped across the top of the uprights 2, 2 and 3, 3 by Stud bolts 19 threaded into the tapped holes 8, and are spaced from the uprights and bus bars 9 and 12 by insulation shims 2O interposed therebetween.

'll he ends of the base plate 1 are splined to form pairs of prongs 21, 21 and 22, 22', between which extend the terminal contacts 23, and 23 of opposite polarity. rlhe terminal d extending laterally therefrom.

contacts, which are shown as consisting of four plates but which may be of any desired number, are alternately disposed with reterence to the bus bars 9 and 12 at right angles thereto in a vertical plane and are held in spaced relation thereto by the metal spacing washers 24 interposed between the plates. Insulation plates 25 having holes 25 therein separate the terminal contact members from electrical Contact with the interior side walls of the prongs 21, 21 vand 22, 22 of the base plate. The prongs 21, 21 and 22, 22 each have vertical end ribs 26 extending laterally therefrom, and horizontal top ribs 27, 27 The holes 28 bored through the vertical walls 21 and 22, respectively, of the prongs receive cylindrical headed bolts 29 which pass through the holes 25 in the insulation plates and through the insulation sleeves 30 positioned in thc holes 31, 31 in the terminal contact elements 23, 23 respectively, and spacing washers 24 to hold thesame separated in fixed position. The cylindrical heads 29 of the bolts 29 are seated in the holes 28 in the vertical walls 21,

22 and bear against the insulation plates 25 against the outer terminal contacts. Nuts threaded on the outer ends ot the bolts 29 draw the assembly against the walls 21, 22 of the prongs. he terminal contact plates 23 and 23 alsoare split and bowed'outwardly to provide a resilient construction.

A rectangular recess 33 is cut out at the ends of the terminal contacts 2323, the purpose oi which will now be described. The base plate has a rabbet 33 extending along each end thereoi2 and grooves34, 34 extending across the top ribs 27 rof the end prongs. Bars 35` surrounded on all sides by insulation material 36 extend horizontally in insulation contact with the contact members 23, 23 and top ribs 27, and assist in supporting the contact members against downward displacement, thereby relieving the downward thrust on bolts 29.

Suitably clamped to the end ribs at one endl arethe pair of auxiliary supports 37, 37 which are right and left and carry similar pairs of uprights, 38, 38 and 39, 39. The uprights 38, 38, 39, 39 are the same in con struction as uprights 2, 2 and 3, 3, and comprise vertical interior walls 40, 40 and 41, 41, respectively, having holes 42, 42 therein in a-lineinent, and reent'orcing ribs 43 at the sides. Top ribs 44 also extend laterally, and have the tapped holes 45 drilled therein. The end walls 46 of the auxiliary supports are drilled at 47 in alinement with the bores 48 in the end ribs 26 of the base plate. Bolts 49 hold the auxiliary supports in position at the ends of the base plate. Insulation plates 54 are interposed between the bottom walls 50 and bus bars 9 and 12, to prevent electrical contact between the Cylindrical headed bolts 51 pass through the holes in insulation plates 56 and through the sleeves 52 in the holes 53, 53 in the bus bars 9 and 12, respectively, and through the metal spacing washers 55 to assist in holding the bus bars in position. The round heads 51 of the bolts 51, pass through the holes 42 to bear against the insulation plates 56. Nuts threaded on the outer end of the bolts 51 draw the assembly against the walls 40 and 41, respectively. Insulation plates 54 and 56 prevent electrical contact between the auxiliary supports and the bus bars. The bus bars 9 and 12 are further held against vertical displacement by the pair of clamping plates 57, each of which is bored at its outer ends as indicated by the numeral 58. The plates 57 are held clamped across the top of the uprights 37 and 37 by stud bolts 59 threaded into the tapped holes 45 and are spaced from the uprights 38,v

38 and 39, 39 and the bus bars 9 and 12 by the insulation shims 55 interposed therebetween.

At the center of the base plate l through the sides of the top are bored the holes 60 and 60. Sleeves 61 of insulation material are inserted in the holes 60 and 60. The reduced and threaded ends 62 of guide rods 63 inserted in the insulation sleeves 61, are further separated from electrical Contact with the base plate 1 by insulation washers 64, and are held in position by the nuts 65 threaded 011- the ends and electrically insulated from the base plate by insulation washers 64. A cross bar 66 fits over the reduced and threadedl upper ends 67 of the guide rods 63 and is secured in position by the nuts 68 threaded over the ends of the guide rods 63. The construction described provides a yoke designated generally by the numeral 65. The cross bar 66is bored andvtapped at its center tofreceive a, threaded switch operating stem 69 rotatably secured at its lower end to the contactor yoke 70.

The central or main contactor member 70', as shown, comprises a yoke shaped body 70 comprising arms 71 and 71" and guiding lugs 72 laterally extending therefrom, having guide holes 73 therein. At the top of the yoke is an undercut slot 74 which receives the head 75 formed on the lower end of the threaded switch operating stem 69. The head 75 is held against axial displacement by the shoulders 76 of the slot 74 which bear against thrust washers 77 separated by a bronze washer to take up the wear on the parts. Slots 78, cut in the end of the yoke receive the end abutment bars 79, which are held in place by the llistered cap screws 80, threaded into the yoke 70. Holes 81 and 81 pass in alinement centrally through the arms of the yoke.

The knives of the switch consist of a series of longitudinally and vertically split plates 82 which are slightly downwardly tapered and are clamped together by the round headed bolt 83 which passes through the insulation sleeve 84:, which in turn passes through the holes 86 in the knife blades 82 and spacing washers 87, and hole 81 in the yoke to hold the contactor knives in spaced position. The round head 83 of the bolt 83 passes through hole 81 in the yoke arm and bears against the side half blade 82. A nut threaded on the outer end of the bolt 83 draws the assembly against the yoke arm 71.

Secondary contactor members 8.8 and 89 are similarly constructed and are similarly mounted in the yokes formed by the side posts 90, 90 secured in the holes 91 and 91 bored in the top webs 27 and 27 at each end of the base plate 1. The construction of the secondary contactor members 88 and 89 is identical with that of main contactor member 70 except for the number of knives 92 and 92 in the yokes and their spacing, which may be varied, as is readily apparent. The contactor members are operated by hand wheels, on the opposite ends of the operating stems 69, not shown, which are suitably insulated electrically from the operating stems 69.

In operation, the secondary contactor members 88 and 89 are in their lowered position, causing the knives 92 to establish electrical contact between the bus bars 9 and terminal contacts 23, and bus bars 12 and terminal contacs 23. The main contactor is held at its retracted position out of contact with the bus bars 9 and 12. It is evident that a current will flow through the bus bars 9, knives 92, terminal contacts 23, to one terminal 93 of the electrolytic cell or other electrical apparatus designated generally by the numeral 93, through the electrical apparatus 93, and from the other terminal 9-1 of the electrical apparatus to the terminal contacts 23', knives 92 and bus bars 12. When it is desired to cut out the electrical apparatus 93 from the circuit, the main contactor 70 is lowered by rotating the operating stem G9 until the blades 82 are forced into contact with the bus bars 9 and 12, short circuiting the apparatus. The secondary contactors 88 and 89 are then withdrawn to retracted position without danger of flashing, taking the knives 92 and 92 out of contact with the bus bars 9 and terminal contacts 23, and bus bars 12 and terminal contacts 23', respectively. To reinsert the apparatus 93 in the circuit, the secondary contactors are lowered till the blades 92 and 92 complete the circuit between bus bars 9 and terminal contacts and bus bars 12 and terminal contacts 23, whereupon the main contactor is withdrawn to retracted position.

Having described my invention, what l claim as new and desire to secure by Letters Patent is:

1. An electric switch comprising a base plate, main bus bars of opposite polarity sealternate bus bars to establish or break electrical connection between the same.

3. An electric switch comprising a base plate, main bus bars of opposite polarity secured to the base plate in insulated contact therewith, terminal contact members alternately spaced between the bus bars out of electrical contact therewith and lineally movable contactor members movable into and out of contact with the respective bus bars and terminal contact members to establish or break electrical contact therebetween.

et. An electric switch comprising a base plate, main bus bars of opposite polarity secured to the base plate and electrically insulated from each other, a yoke member lineally movable with relation to the base plate, spaced contactor blades carried by the yoke, and means for moving the yoke and spaced contactor blades into operative position to electrically connect the main bus bars.

5. An electric switch comprising a base plate, main conductors of opposite polarity secured to the base plate and electrically insulated from each other, a feeder conductor out of electrical contact with a main conductor, a main contactor for electrically connecting said main conductors with each other, means for moving said contactor into and out of electrical contact with said main conductors, a secondary contactor for electrically connecting said feeder conductor with a main conductor, and means for moving said secondary contactor into and out of electrical Contact with said main conductor and feeder conductor.

6. An electric switch comprising a base plate, main bus bars of opposite polarity secured to the base plate and electrically insulated from each other, terminal contact elements alternately spaced between the bus bars out of electrical contact therewith, a main contactor element comprising a series of spaced blades, secondary contactor elements comprising series of spaced blades, means for moving the main contactor element blades into and out of electrical contact with the main bus bars, and means for moving the secondary contactor element blades into and out of contact with the respective bus bars and terminal contact elements. i

7. An electric switch comprising a base plate, having upright supports at the sides thereof, main bus bars of opposite polarity held in fixed spaced relation between the nprights and electrically insulated from each other, terminal contact elements alternately spaced between the bus bars out of electrical Contact therewith, a plurality of yokes mounted on the base plate,.main and secondary contactors slidably mounted in said yokes, said main andV secondary contactors comprising yokes carrying knife blades, means for moving the main contactor knife blades into and out of electrical Contact with the main bus bars, and means for moving the secondary contactor knife blades into and out of contact with the respective bus bars and terminal contact elements.

8. An apparatus as defined in claim 7 wherein the main and secondary contactor knife blades are vertically tapered and split longitudinally and bowed to provide resilient wedges.

9. An electric switch comprising a base plate having upright supports at its sides' and being splined at its ends, split and bowed main bus bars of opposite polarity alternately spaced and held in spaced relation against upright supports on one side of the base plate, split terminall Contact elements located in the splined ends of the base plate and alternately disposed and held at said side of the base plate in spaced relation to the main bus bars out of electrical contact therewith, main and secondary contactors comprising yokes carrying spaced split knives, means for moving the main contactor knife blades into'and out of electrical contact with the main bus bars, and means for moving the secondary contactor knives into and out of contact with the respective bus bars and terminal contact elements.

JOSEPH E. JEWET'T. 

